The methods and systems of the present invention are directed to the modification and improvement of transmissions for automotive vehicles, more commonly referred to as “factory installed” transmissions, installed in automotive vehicles by an original motor vehicle manufacturer. The invention is more particularly directed to improvements to “factory installed” transmissions for the Toyota and Lexus vehicles equipped with A750E, A750F, and A761E “Factory Installed Transmissions”.
The present inventor is the inventor identified in the following United States patents and published patent application, the disclosures of which are expressly incorporated by reference into the present patent application: U.S. Pat. No. 4,449,426, issued May 26, 1984; U.S. Pat. No. 4,711,140, issued Dec. 8, 1987; U.S. Pat. No. 4,790,938, issued Dec. 13, 1988; U.S. Pat. No. 5,253,549; issued Oct. 19, 1993; U.S. Pat. No. 5,540,628, issued Jul. 30, 1996; U.S. Pat. No. 5,624,342; issued Apr. 29, 1997; U.S. Pat. No. 5,730,685, issued Mar. 24, 1998; U.S. Pat. No. 5,743,823, issued Apr. 28, 1998; U.S. Pat. No. 5,768,953, issued Jun. 23, 1998; U.S. Pat. No. 5,820,507, issued Oct. 7, 1998; U.S. Pat. No. 5,967,928, issued Oct. 19, 1999; U.S. Pat. No. 6,099,429, issued Aug. 8, 2000; U.S. Pat. No. 6,117,047, issued Sep. 12, 2000; U.S. Pat. No. 6,287,231, issued Sep. 11, 2001; U.S. Pat. No. 6,390,944, issued May 21, 2002; U.S. Pat. No. 6,565,472, issued May 20, 2003; U.S. Pat. No. 6,699,157, issued Mar. 2, 2004; U.S. Pat. No. 6,729,989, issued May 4, 2004; U.S. Pat. No. 6,814,680, issued Nov. 9, 2004; U.S. Pat. No. 6,871,397, issued Mar. 29, 2005; U.S. Pat. No. 6,913,554, issued Jul. 5, 2005; U.S. Pat. No. 6,964,628, issued Nov. 15, 2005; U.S. Pat. No. 7,128,679, issued Oct. 31, 2006; U.S. Pat. No. 7,331,893, issued Feb. 19, 2008; and US2013/0037134, published on Feb. 14, 2013.
It is the primary object of the present invention to modify the “factory installed” transmissions for the A750E, A750F and A761E transmission installed in Toyota and Lexus vehicles to improve the overall operation and efficiency of these “factory installed” automotive transmissions. The modifications to the “factory installed” transmissions, as more fully described herein, include modification of the torque converter charge circuit by enlarging the original inner valve bore to restore pressure in the converter apply circuit to avoid cross leaks with the exhaust circuit, and replacing the original lock up control valve plunger and bushing to avoid leaks in torque converter charge circuit.
Other objects and advantages of the modification to the “factory installed” automotive transmissions in accordance with the present invention will become apparent from the following description in conjunction with the drawings.